Canister



FIG. 1 is a perspective view of a canister showing our design;

FIG. 2 is a front elevational thereof;

FIG. 3 is a top elevational view thereof; and,

FIG. 4 is a bottom elevational view thereof.

The broken lines in the figures are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a canister, as shown and described. 